import java.util.Scanner;

public class Main {
public static int binarySearch(int[] arr, int x) {
int low = 0; 
int high = arr.length-1; 
while(low <= high) { 
int middle = (low + high)/2; 

if(x == arr[middle]) { 
return middle; 
}else if(x <arr[middle]) { 
high = middle - 1; 
}else { 
low = middle + 1; 
} 
} 
return high;
}

public static void main(String[] args) {
int[] arr = {1,2,3,4,5,6,7,8,9,10 };
Scanner input = new Scanner(System.in);
int number = input.nextInt();
if(number < arr[0] || number > arr[arr.length-1]) {
System.out.println("not found");
}
else{
System.out.println("weizhi:" + (binarySearch(arr, number) ));
}

}
}

 